Need to automate testing of a multipage web form using cucumber or similar tools

Hi, I have a wordpress site that contains a fairly complex web form (it's using gravity forms if that matters to you). Although we are moving away from Wordpress we need to automate testing of this company critical form so that when changes are made by staff or developers it can quickly be tested and verified as working without the need to have developers and admins spend time manually testing it out. Gravity forms dumps everything into a single big page, but submits the correct form via a URL variable - but other than that the form is a pretty straight-forward web form. It is around 8 pages (this changes frequently). The gist is that I would like to automate the testing of this page using something like Cucumber (if you have suggestions on other tools then please let me know so I can review, i.e. webrat, capybara etc...). I will likely want to run this as part of the code deployments, but would also like to have the option to run this manually if a problem is suspected or someone changes things via the admin panel. I'm fairly partial to Ruby for things like this. Please respond with your proposals, a brief introduction and a github/bitbucket account I can checkout with similar work. I don't expect this to take longer than a half a day to a full day for someone with proper experience but the more detailed your proposal (i.e. canned responses will be removed) the better it will be for both of us.